.\" Copyright (c) 2001-2003 Leon Bottou, Yann Le Cun, Patrick Haffner,
.\" Copyright (c) 2001 AT&T Corp., and Lizardtech, Inc.
.\"
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.\" modify it under the terms of the GNU General Public License as
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.\" You should have received a copy of the GNU General Public
.\" License along with this manual. Otherwise check the web site
.\" of the Free Software Foundation at http://www.fsf.org.
.TH DJVUSED 1 "5/22/2005" "DjVuLibre-3.5" "DjVuLibre-3.5"
.de SS
.SH \\0\\0\\0\\$*
..
.SH NAME
djvused \- Multi-purpose DjVu document editor.

.SH SYNOPSIS
.BI "djvused [" "options" "] " "djvufile"


.SH DESCRIPTION
Program
.B djvused 
is a powerful command line tool for manipulating multi-page documents,
creating or editing annotation chunks, creating or editing hidden text layers, 
pre-computing thumbnail images, and more.  
The program first reads the DjVu document
.I djvufile
and executes a number of djvused commands.

Djvused commands can be read from a specific file (when option
.B -f
is specified), read from the command line (when option
.B -e
is specified), or read from the standard input (the default).

.SH OPTIONS
.TP
.BI "-v"
Cause 
.B djvused 
to print a command line prompt before reading commands
and a brief message describing how each command was executed.
This option is very useful for debugging djvused scripts
and also for interactively entering djvused commands on
the standard input.
.TP
.BI "-f " "scriptfile"
Cause
.B djvused
to read commands from file
.IR scriptfile .
.TP
.BI "-e " "command"
Cause
.B djvused
to execute the commands specified by the option argument
.IR commands .
It is advisable to surround the djvused commands by single
quotes in order to prevent unwanted shell expansion.
.TP
.BI "-s"
Cause 
.B djvused
to save the file 
.I djvufile
after executing the specified commands.
This is similar to executing command
.B save
immediately before terminating the program.
.TP
.BI "-u"
Cause
.B djvused
to print hidden text and annotations as UTF-8 
instead of encoding non-ASCII characters with octal escape sequences
for maximal portability. This option is convenient for 
manually editing or viewing the djvused output.
This option also causes the emission of an UTF-8 BOM under Windows.
.TP
.BI "-n"
Cause 
.B djvused 
to disregard save commands.
This is useful for debugging djvused scripts
without overwriting files on your disk.

.SH DJVUSED EXAMPLES
There are many ways to use program
.BR djvused .
The following examples illustrate 
some common uses of this program.

.SS Obtaining the size of a page
Command 
.B size 
outputs the width and height of the selected pages
using a
.SM HTML
friendly syntax. 
For instance, the following command prints the size 
of page
.I 3
of document
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'select 3; size'"
.PP

.SS Extracting the hidden text
Command
.B print-pure-txt
outputs the text associated with a page or a document.
For instance, the following shell command outputs the text
for the entire document.  Lines and pages are delimited
by the usual control characters.
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'print-pure-txt'"
.PP
Command
.B print-txt
produces a more extensive output describing the structure
and the location of the text components.  The syntax of this
output is described later in this man page.  For instance, 
the following shell command outputs extended text information
for page 
.I 3 
of document
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'select 3; print-txt'"
.PP

.SS Extracting the annotations
Annotation data can be extracted using command 
.BR print-ant .
The syntax of the annotation data is described later in this man page.
For instance, the following shell command outputs the annotation data
for the first page of document
.BR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'select 1; print-ant'"
.PP
Command 
.B print-ant
only prints the annotations stored in the selected component file.
Command
.B print-merged-ant
also retrieves annotations from all the component files 
referenced by the current page (using 
.SM INCL
chunks) and prints the merged information.

.SS Dumping/restoring annotations and text
Three commands,
.BR "output-txt" ", " "output-ant" ", and " "output-all" ","
produce djvused scripts.  For instance, the following shell command
produces a djvused script,
.IR myfile.dsed ,
that recreates all the text and annotation data
in document
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'output-all' > " "myfile.dsed"
.PP
Script
.I myfile.dsed
is a text file that can be easily edited.  The following shell command
then recreates the text and annotation information in file
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -f " "myfile.dsed" " -s"

.SS Extracting a page
Both commands
.B save-page
and
.B save-page-with
create a DjVu file representing the selected component file of a
document.  The following shell command, for instance, creates a file
.I p05.djvu
containing page
.I 5
of document
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'select 5; save-page " "p05.djvu" "'"
.PP
Each page of a document might import data from 
another component file using the so-called inclusion (
.SM INCL
) chunks.  Command
.B save-page
then produces a file with unresolved references to imported data.  
Such a file should then be made part of a multi-page document
containing the required data in other component files.
On the other hand, command 
.B save-page-with
copies all the imported data into the output file.
This file is directly usable. Yet collecting several
such files into a multi-page document might lead
to useless data replication.

.SS Pre-computing thumbnails
Commands 
.B set-thumbnails
constructs thumbnails that can be later displayed by
DjVu viewers.  The following shell command, for instance,
computes thumbnails of size 
.IR 64 x 64
pixels for all pages of file
.IR myfile.djvu .
.IP "" 3
.BI "djvused " "myfile.djvu" " -e 'set-thumbnails 64' -s"

.SH DJVUSED COMMANDS
Command lines might contain zero, one, or more djvused commands and an
optional comment.  Multiple djvused commands must be separated by a
semicolon character ';'.  Comments are introduced by the '#' character
and extend until the end of the command line.

.SS Selection commands
Multi-page DjVu documents are composed of a number of component files.
Most component files describe a specific page of a document.  Some
component files contain information shared by several pages such as
shared image data, shared annotations or thumbnails.  Many djvused
commands operate on selected component files.  All component files are
initially selected.  The following commands are useful for changing
the selection.
.TP
.BI "n"
Print the total number of pages in the document.
.TP
.BI "ls"
List all component files in the document.  Each line contains an
optional page number, a letter describing the component file type, the
size of the component file, and identifier of the component file.
Component file type letters
.BR P ", " I ", " A ", and " T 
respectively stand for page data, shared image data, shared annotation
data, and thumbnail data.  Page numbers are only listed for component
files containing page data.  
When it is set, the optional page title (see command
.B "set-page-title"
below) is displayed after the component file identifier.
.TP
.BI "select [" "fileid" "]"
Select the component file identified by argument
.IR fileid .
Argument 
.I fileid
must be either a page number or a component file identifier.
The
.B select
command selects all component files
when the argument
.I fileid
is omitted.
.TP
.BI "select-shared-ant"
Select a component file containing shared annotations.  
Only one such component file is supported by the current DjVu software. 
This component file usually contains annotations pertaining to the 
whole document as opposed to specific pages.  An error message 
is displayed if there is no such component file.
.TP
.BI "create-shared-ant"
Create and select a component file containing shared annotations.
This command only selects the shared annotation component file if such
a component file already exists.  Otherwise it creates a new shared
annotation component file and makes sure that it is imported by all
pages in the document.
.TP
.BI "showsel"
Shows the currently selected component files
with the same format as command
.BR ls .

.SS Text and annotation commands
.TP
.BI "print-pure-txt"
Print the text stored in the hidden text layer of the selected pages.
A similar capability is offered by program
.BR djvutxt .
Structural information is sometimes represented by control characters.
Text from different pages is delimited by form feed characters
("\\f").  Lines are delimited by newline characters ("\\n").  Columns,
regions, and paragraphs are sometimes delimited by vertical tab
("\\013"), group separators ("\\035") and unit separators ("\\037")
respectively.
.TP
.BI "print-txt"
Prints extensive hidden text information for the selected pages.
This information describes the structure of the text on the 
document page and locates the structural elements in the page image.
The syntax of this output is described later in this man page.
.TP
.BI "remove-txt"
Remove the hidden text information from the selected component files.
For instance, executing commands
.BR "select" " and " "remove-txt"
removes all hidden text information from the DjVu document.
.TP
.BI "set-txt [" "djvusedtxtfile" "]"
Insert hidden text information into the selected pages.
The optional argument
.I djvusedtxtfile
names a file containing the hidden text information.
This file must contain data similar to what is produced
by command
.BR print-txt . 
When the optional argument is omitted, the
program reads the hidden text information from the djvused script
until reaching an end-of-file or a line containing a single period.
.TP
.BI "output-txt"
Prints a djvused script that reconstructs the hidden text
information for the selected pages.  This script can later
be edited and executed by invoking program
.B djvused
with option
.BR -f .
.TP
.BI "print-ant"
Prints the annotations of the selected component file.
The annotation data is represented using a simple syntax
described later in this document.
.TP
.BI "print-merged-ant"
Merge the annotations stored in the selected component files
with the annotations imported from other component files such
as the shared annotation component file..
The annotation data is represented using a simple syntax
described later in this document.
.TP
.BI "remove-ant"
Remove the annotation information from the selected component files.
For instance, executing commands
.BR "select" " and " "remove-ant"
removes all annotation information from the DjVu document.
.TP
.BI "set-ant [" "djvusedantfile" "]"
Insert annotations into the selected component file.
The optional argument
.I djvusedantfile
names a file containing the annotation data.
This file must contain data similar to what is produced
by command
.BR print-ant . 
When the optional argument is omitted, the
program reads the annotation data from the djvused script itself
until reaching an end-of-file or a line containing a single period.
.TP
.BI "output-ant"
Print a djvused script that reconstructs the annotation
information for the selected pages.  This script can later
be edited and executed by invoking program
.B djvused
with option
.BR -f .
.TP
.BI "print-meta"
Print the metadata part of the annotations for the selected component file.
This command displays a subset of the information printed by command
.B print-ant
using a different syntax.  metadata are organized as key\-value pairs.
Each printed line contains the key name such as
.BR "author" ", " "title" ",etc.,"
followed by a tab character ("\\t") and
a double-quoted string representing the 
.SM UTF-8
encoded metadata value.
.TP
.BI "remove-meta"
Remove the metadata part of the annotations of 
the selected component files.
.TP
.BI "set-meta [" "djvusedmetafile" "]"
Set the metadata part of the annotations of the selected component file.
The remaining part of the annotations is left unchanged.
The optional argument
.I djvusedmetafile
names a file containing the metadata.
This file must contain data similar to what is produced
by command
.BR print-meta . 
When the optional argument is omitted, the
program reads the annotation data from the djvused script itself
until reaching an end-of-file or a line containing a single period.
.TP
.BI "print-xmp"
Print the XMP metadata string contained in 
the annotation chunk of the selected component file.
This command displays in fact a subset of the 
information printed by command
.BR print-ant .
.TP
.BI "remove-xmp"
Removes the XMP tag from the annotation chunk of the selected component file.
.TP
.BI "set-xmp [" "xmpfile" "]"
Set the XMP metadata part of the annotations of the selected component file.
The remaining part of the annotations is left unchanged.
The optional argument
.I xmpfile
names a file containing the XMP metadata in a format 
similar to that produced
by command
.BR print-xmp . 
When the optional argument is omitted, the
program reads the XMP annotation data from the djvused script itself
until reaching an end-of-file or a line containing a single period.
.TP
.BI "output-all"
Print a djvused script that reconstructs both the hidden text and the
annotation information for the selected pages.  This script can later
be edited and executed by invoking program
.B djvused
with option
.BR -f .
.PP
.SS Outline/bookmarks commands
.TP
.BI "print-outline"
Print the outline of the document.
Nothing is printed if the document contains no outline.
.TP
.BI "remove-outline"
Removes the outline from the document.
.TP
.BI "set-outline [" djvusedoutlinefile "]"
Insert outline information into the document.
The optional argument
.I djvusedoutlinefile
names a file containing the outline information.
This file must contain data similar to what is produced
by command
.BR print-outline . 
When the optional argument is omitted, the
program reads the hidden text information from the djvused script
until reaching an end-of-file or a line containing a single period.
.PP
.SS Thumbnail commands
.TP
.BI "set-thumbnails " "sz"
Compute thumbnails of size
.IR sz x sz
pixels and insert them into the document.
DjVu viewers can later display these thumbnails very
efficiently without need to download the data for
each page.  Typical thumbnail size range 
from 48 to 128 pixels.
.TP
.BI "remove-thumbnails"
Remove the pre-computed thumbnails from the DjVu document.
New thumbnails can then be computed using command
.BR set-thumbnails .

.SS Save commands
The above commands only modify the memory image of the DjVu document.
The following commands provide means to save the modified data
into the file system.
.TP
.BI "save"
Save the modified DjVu document back into the input file
.I djvufile
specified by the arguments of the program 
.BR djvused .
Nothing is done if the DjVu file was not modified.
Passing option
.B -s
program
.B djvused 
is equivalent to executing command
.B save
before exiting the program.
.TP
.BI "save-bundled " "filename"
Save the current DjVu document as a bundled 
multi-page DjVu document named 
.IR filename .
A similar capability is offered by program
.BR djvmcvt .
.TP
.BI "save-indirect " "filename"
Save the current DjVu document as an indirect
multi-page DjVu document.  The index file of the
indirect document will be named 
.BR filename .
All other files composing the indirect document
will be saved into the same directory as the
index file.
A similar capability is offered by program
.BR djvmcvt .
.TP
.BI "save-page " "filename"
Save the selected component file into DjVu file
.IR filename .
The selected component file might import data from 
another component file using the so-called inclusion (
.SM INCL
) chunks.  This command then produces a file with unresolved
references to imported data.  Such a file should then be made part of
a multi-page document containing the required data in other component
files.
.TP
.BI "save-page-with " "filename"
Save the selected component file into DjVu file
.IR filename .
All data imported from other component files is copied into the output
file as well.  This command always produces a usable DjVu file.  On
the other hand, collecting several such files into a multi-page
document might lead to useless data replication.

.SS Miscellaneous commands
.TP
.BI "help"
Display a help message listing all commands supported by
.BR djvused .
.TP
.BI "dump"
Display the 
.SM EA IFF 85
structure of the document or of the selected component file.
A similar capability is offered by program
.BR djvudump .
.TP
.BI "size"
Display the width and the height of the selected pages.  The
dimensions of each page are displayed using a syntax suitable for
direct insertion into the
.SM <EMBED...></EMBED>
tags. This command also displays the default page orientation
when it is different from zero.
.TP
.BI "set-rotation [+-]" "rot"
Changes the default orientation of the selected pages.
The orientation is expressed as an integer in range 0..3
representing a number of 90 degree counter-clockwise rotations.
When the argument is preceded by a sign
.BR "+" " or " "-" ","
argument
.I rot
counts how many additional 90 degree counter-clockwise rotations
should be applied to the page. Otherwise, argument
.I rot
represents the desired absolute page orientation.
Only DjVu pages can be rotated.
Pages represented as a raw IW44 image cannot be rotated.
.TP
.BI "set-dpi " "dpi"
Sets the resolution of the page image in dots per inche.
Argument
.I dpi
should be in range 25..6000.
.TP
.BI "set-page-title " "title"
Sets a page title for the selected page.
When page titles are available, recent versions 
of the DjVuLibre viewers display these page
titles instead of page numbers and also 
accept them in page selection options.
Command
.B "ls"
can be used to see both the page titles and page identifiers.
To unset a page title, simply make it equal to the page identifier.

.SH DJVUSED FILE FORMATS

Djvused uses a simple parenthesized syntax to represent
both annotations and hidden text.
.IP "*" 3
This syntax is the native syntax used by DjVu for storing annotations.
Program
.B djvused
simply compresses the annotation data using the
.BR bzz (1)
algorithm.
.IP "*" 3
This syntax differs from the native syntax used by DjVu for
storing the hidden text.  Program 
.B djvused
performs the translations between the compact binary representation
used by DjVu and the easily modifiable parenthesized syntax.
.PP

.SS General syntax
Djvused files are
.SM ASCII
text files.  The legal characters in djvused files are 
the printable 
.SM ASCII 
characters and the space, tab, cr, and nl characters.
Using other characters has undefined results.

Djvused files are composed of a sequence of expressions separated by
blank characters (space, tab, cr, or nl).  There are four kind of
expressions, namely integers, symbols, strings and lists.
.IP Integers:
Integer numbers are represented by one or more digits,
with the usual interpretation.
.IP Symbols:
Symbols, or identifiers, are sequences of printable ascii characters
representing a name or a keyword.  Acceptable characters are the alpha-numeric
characters, the underscore "_", the minus character "-", and the hash
character "#".  Names should not begin with a digit or a minus character.
.IP Strings:
Strings denote an arbitrary sequence of bytes,
usually interpreted as a sequence of 
.SM UTF-8
encoded characters.  Strings in djvused files are similar to strings in the C
language.  They are surrounded by double quote characters.  Certain sequences
of characters starting with a backslash ("\\") have a special meaning.  
A backslash followed by letter
"a", "b", "t", "n", "v", "f", "r", "\\", and \"
stands for the ascii character BEL(007), BS(008), HT(009),
LF(010), VT(011), FF(012), CR(013), BACKSLASH(134) 
and DOUBLEQUOTE(042) respectively.
A backslash followed by one to three digits stands for the byte 
whose octal code is expressed by the digits.  
All other backslash sequences are illegal.
All non printable ascii characters must be escaped.
.IP Lists:
Lists are sequence of expressions separated by blanks and surrounded by
parentheses.  All expressions types are acceptable within a list, including
sub-lists.

.SS Hidden text syntax
The building blocks of the hidden text syntax are lists
representing each structural component of the hidden text.
Structural components have the following form:
.IP "" 3
.BI "(" "type" " " "xmin" " " "ymin" " " "xmax" " " "ymax" " ... )"
.PP

The symbol
.I type
must be one of 
.BR page ", " column ", " region ", " para ", " line ", " word ", or " char ,
listed here by decreasing order of importance.  
The integers
.IR xmin ", " ymin ", " xmax ", and " ymax
represent the coordinates of a rectangle indicating the position of the
structural component in the page.  Coordinates are measured in pixels and have
their origin at the bottom left corner of the page.  The remaining expressions
in the list either is a single string representing the encoded text associated
with this structural component, or is a sequence of structural components with
a lesser type.
.PP
The hidden text for each page is simply represented by
a single structural element of type
.BR page .
Various level of structural information are acceptable.  For instance, the
page level component might only specify a page level string, or might only
provide a list of lines, or might provide a full hierarchy down to the
individual characters.

.SS Outline/Bookmark syntax
The outline syntax is a single list of the form
.IP "" 3
.BI "(bookmarks ...)"
.PP
The first element of the list is symbol
.BR bookmarks .
The subsequent elements are lists representing
the toplevel outline entries.
Each outline entry is represented by
a list with the following form:
.IP "" 3
.BI "(" title " " url " ... )"
.PP
The string 
.I title
is the title of the outline entry.
The destination string
.I url
can be either an arbitrary percent encoded
.SM URL,
or composed of the hash character ("#")
followed by a page name or number,
or composed of the question mark character ("?")
followed by cgi-style arguments interpreted by the djvu viewer.
The remaining expressions in the list
describe subentries of this outline entry.

.SS Annotation syntax
Annotations are represented by a sequence of annotation expressions.
The following annotation expressions are recognized:
.TP
.BI "(background " color ")"
Specify the color of the viewer area surrounding the DjVu image.
Colors are represented with the X11 hexadecimal syntax
.BR #RRGGBB .
For instance, 
.B #000000
is black and
.B #FFFFFF
is white.
.TP
.BI "(zoom " zoomvalue ")"
Specify the initial zoom factor of the image.
Argument
.I zoomvalue
can be one of
.BR stretch ", " one2one ", " width ", " page ", "
or composed of the letter
.B d
followed by a number in range 1 to 999 representing a zoom factor
(such as in
.BR d300 " or " d150
for instance.)
.TP
.BI "(mode " modevalue ")"
Specify the initial display mode of the image.
Argument
.I modevalue
is one of
.BR color ", " bw ", " fore ", or " back "."
.TP
.BI "(align " horzalign " " vertalign ")"
Specify how the image should be aligned on the viewer surface.
By default the image is located in the center.  
Argument 
.I horzalign
can be one of
.BR left ", " center ", or " right "."
Argument 
.I vertalign
can be one of
.BR top ", " center ", or " bottom "."
.TP
.BI "(maparea " url " " comment " " area " ...)"
Define an hyper-link for the specified destination.
.RS
.PP
Argument
.I url
can have one of the following forms:
.IP "" 3
.I href
.br
.BI "(url " href " " target ")" 
.br
.PP
where 
.I href
is a string representing the destination and 
.I target 
is a string representing the target frame for the hyper-link,
as defined by the 
.SM HTML
anchor tag
.SM <A>.
The destination string
.I href
can be either an arbitrary percent encoded
.SM URL,
or composed of the hash character ("#")
followed by a page name or number,
or composed of the question mark character ("?")
followed by cgi-style arguments interpreted by the djvu viewer.
Page numbers may be prefixed with an optional sign 
to represent a page displacement.  
For instance the strings
.B """#-1""" 
and 
.B """#+1"""
can be used to access the previous page and 
the next page.

Argument 
.I comment 
is a string that might be displayed by the viewer 
when the user moves the mouse over the hyper-link.

Argument
.I area
defines the shape and the location of the hyperlink.
The following forms are recognized:
.IP "" 3
.BI "(rect " xmin " " ymin " " width " " height ")"
.br
.BI "(oval " xmin " " ymin " " width " " height ")"
.br
.BI "(poly " x0 " " y0 " " x1 " " y1 " ... )"
.br
.BI "(text " xmin " " ymin " " width " " height ")"
.br
.BI "(line " x0 " " y0 " " x1 " " y1 ")"
.PP
All parameters are numbers representing coordinates.  
Coordinates are measured in pixels and have their origin 
at the bottom left corner of the page.

The remaining expressions in the
.B maparea
list represent the visual effect associated with
the hyper-link. 

A first set of options defines how borders
are drawn for 
.BR rect ", " oval ", " polygon ", or " text 
hyperlink areas.
.IP "" 3
.BI "(none)"
.br
.BI "(xor)"
.br
.BI "(border " color ")"
.br
.BI "(shadow_in [" thickness "])"
.br
.BI "(shadow_out [" thickness "])"
.br
.BI "(shadow_ein [" thickness "])"
.br
.BI "(shadow_eout [" thickness "])"
.PP
where parameter 
.I color
has syntax
.B #RRGGBB
as described above,
and parameter thickness is an integer in range 1 to 32.
The last four border options are only supported for 
.B rect
hyperlink areas. 
Although the border mode defaults to   
.BR (xor) ,
it is wise to always specify the border mode.
Border options do not apply to 
.B line 
areas.

When a border option is specified, the border 
becomes visible when the user moves the mouse 
over the hyperlink. The border may be made
always visible by using the following option:
.IP "" 3
.B (border_avis)
.PP
The following two options may be used with 
.B rect
hyperlink areas.
The complete area will be highlighted using the 
specified color at the specified opacity (0-100, default 50).
.IP "" 3
.BI "(hilite " color ")"
.br
.BI "(opacity " op ")"
.PP
This is often used with an empty 
.SM URL 
for simply emphasizing a specific
segment of an image.
.PP
The following three options may be used with line areas to 
specify an optional ending arrow, the line width and color.
The default is a black line with width 1 and without arrow.
.IP "" 3
.B "(arrow)"
.br
.BI "(width " w ")"
.br
.BI "(lineclr " color ")"
.PP
Finally the following three options can be used with text areas.
The default background color is transparent. 
The default text color is black.
The 
.B pushpin
option indicates that the text is symbolized by a small pushpin icon.
Clicking the icon reveals the text.
.IP "" 3
.BI "(backclr " bkcolor ")"
.br
.BI "(textclr " txtcolor ")"
.br
.BI "(pushpin)"
.PP

.RE
.TP
.BI "(metadata ... (" key " " value ") ... )"
Define metadata entries.
Each entry is identified by a symbol
.I key
representing the nature of the meta data entry.
The string
.I value
represents
the value associated with the corresponding key.
Two sets of keys are noteworthy:
keys borrowed from the BibTex bibliography system,
and keys borrowed from the PDF DocInfo metadata.
BibTex keys are always expressed in lowercase, such as
.BR year ", " booktitle ", " editor ", " author ", etc.."
DocInfo keys start with an uppercase letter, such as
.BR Title ", " Author ", " Subject ", " Creator ", "
.BR Produced ", " Trapped ", "
.BR CreationDate ", and " ModDate "."
The values associated with the last two keys
should be dates expressed according to RFC 3339.

.SH LIMITATIONS
The current version of program 
.B djvused
only supports selecting one component file
or all component files.  There is no way to
select only a few component files.

.SH CREDITS
This program was initially written by L\('eon Bottou
<leonb@users.sourceforge.net> and was improved by Yann Le Cun
<profshadoko@users.sourceforge.net>, Florin Nicsa, Bill Riemers
<docbill@sourceforge.net> and many others.

.SH SEE ALSO
.BR djvu (1),
.BR djvutxt (1),
.BR djvmcvt (1),
.BR djvudump (1),
.BR bzz (1),
Emacs djvused front end \fBdjvu.el\fR on
.SM GNU Elpa
repository.
